Tumors of the heart are rare. A large series of autopsy reports (approximately 40,000 cases) show that metastatic growths in the heart occur in approximately 0.5 per cent of cases, whereas primary tumors are found in 0.03 per cent (Yater1 and Mead2). On the other hand, studies of cases of malignant growth with disseminated metastases reveal an incidence of about 7.5 per cent in cases of cardiac involvement (Yater,1 Burke3). Metastatic tumors have been reported as diagnosed during life in only 10 cases, the first by Roesler,4 in 1924, and all the others since 1930 (Heninger,5 Willius and Amberg,6 Fishberg,7 Schnitker and Bailey,8 Doane and Solis-Cohen,9 Smith10). Such tumors may involve any part of the heart, but especially the right auricle. They have been described as arising from almost any type of malignant tumor anywhere in the body. Usually they produce no symptoms and are found